17–22 May 2026
C.I.D
Europe/Zurich timezone

Ultra-Fast Slow Extraction from HIRFL-CSRm Using Autoresonance

WEP4657
20 May 2026, 16:00
2h
C.I.D

C.I.D

Deauville, France
Board: Wednesday baguette: BG02
Poster Presentation MC4.T12: Hadron accelerators: Beam Injection/Extraction and Transport Poster session

Speaker

Mr Siji Li (Institute of Modern Physics, Chinese Academy of Sciences)

Description

To meet the demand for high-intensity ion beams in FLASH radiotherapy and materials science, achieving millisecond-scale ultra-fast slow extraction from synchrotrons is a critical challenge. Conventional slow extraction methods, such as RF-KO, take seconds and are inadequate for FLASH's requirement of >40 Gy/s dose rates. Overcoming this requires innovative beam dynamics based on Autoresonance. Autoresonance is a nonlinear phenomenon where particles become phase-locked to a sweeping frequency drive, causing their amplitudes to grow together in sync. Unlike conventional RF-KO, which randomly fills phase space, Autoresonance creates a "hollow beam" profile. To achieve this, strong nonlinearities are essential. Based on the HIRFL-CSRm lattice, this research proposes introducing octupole magnets to work alongside existing sextupoles, thereby strengthening the detuning coefficient and lowering the Autoresonance threshold. Single-cycle frequency sweep excitation was simulated to induce rapid and controlled beam spill. This approach will be modeled using the HIRFL-CSRm lattice to explore the impact of sextupole resonance strength and octupole-induced detuning on the Autoresonance condition. Success will be experimentally validated onHIRFL-CSRm, paving the way for FLASH cancer therapy and advanced nuclear materials testing.

Paper status No proceeding file submitted.

Author

Mr Siji Li (Institute of Modern Physics, Chinese Academy of Sciences)

Presentation materials

There are no materials yet.